It's a common mistake to assume that chomp takes a value, chomps it, and returns the result, but this isn't the case; chomp operates on the expression you feed it. In particular, that expression has to be an lvalue.

You'll have to save your command's output in a variable to chomp it, which I think will also make your code more readable. :) You can chomp and assign in the same step, e.g.: 

foreach my $min (20 .. 29) {
    foreach my $sec (@seconds) {
        chomp(my $res = `cut -d "|" -f 1,10,13 SMSCDR*$date$hour$minut
+e*.log |grep "Submit|SMPP" |grep "$hour:$min:$sec" |sort |uniq -c`);
        my $SMPP_count = (split /\s+/, $res)[0];
        print $SMPP_count;
    }
}

[download]

Though for the sake of readability I'd still suggest separating this a bit further and not doing everything in the same step (the command you're invoking is complicated enough, after all). Meanwhile, this: 

syntax error at second.pl line 24, near ")["

[download]

is because you've got the parentheses in the wrong place. You're doing split(..., ...)[...], trying to treat split as if it were a list, but it isn't. However, if you put what split returns into a list, it works: (split ..., ...)[...]. I've fixed that above.

Finally, you don't need a character class in your regexp you feed to split, though depending on what exactly your command returns, you may want to split on any (positive) amount of whitespace (\s+), not just one whitespace character (\s). I've changed that above as well.

In reply to Re: using system command in regex by AppleFritter
in thread using system command in regex by ravi45722

Title:
Use:  <p> text here (a paragraph) </p>
and:  <code> code here </code>
to format your post, it's "PerlMonks-approved HTML":


  • Posts are HTML formatted. Put <p> </p> tags around your paragraphs. Put <code> </code> tags around your code and data!
  • Titles consisting of a single word are discouraged, and in most cases are disallowed outright.
  • Read Where should I post X? if you're not absolutely sure you're posting in the right place.
  • Please read these before you post! —
  • Posts may use any of the Perl Monks Approved HTML tags:
    a, abbr, b, big, blockquote, br, caption, center, col, colgroup, dd, del, details, div, dl, dt, em, font, h1, h2, h3, h4, h5, h6, hr, i, ins, li, ol, p, pre, readmore, small, span, spoiler, strike, strong, sub, summary, sup, table, tbody, td, tfoot, th, thead, tr, tt, u, ul, wbr
  • You may need to use entities for some characters, as follows. (Exception: Within code tags, you can put the characters literally.)
            For:     Use:
    & &amp;
    < &lt;
    > &gt;
    [ &#91;
    ] &#93;
  • Link using PerlMonks shortcuts! What shortcuts can I use for linking?
  • See Writeup Formatting Tips and other pages linked from there for more info.